Early in the development of modern networking equipment such as routers, it was realized that at times a particular piece of network equipment might hang or “crash.” In such instances, a human operator often had to intervene by traveling to the location of the equipment and rebooting or power cycling the equipment in order to get that particular piece of equipment working. Power cycling and information about consumed power are also of interest in a number of computer equipment and other equipment settings.
The discussion of any work, publications, sales, or activity anywhere in this submission, including in any documents submitted with this application, shall not be taken as an admission that any such work constitutes prior art. The discussion of any activity, work, or publication herein is not an admission that such activity, work, or publication existed or was known in any particular jurisdiction.
A power distribution unit (PDU) can be used to provide power management to a plurality of devices. Referring now to FIG. 30, a block schematic diagram of an apparatus including a conventional PDU for power management to a plurality of devices is set forth and given the general reference character 100.
Apparatus 100 includes a conventional PDU 130 that is connected to a wall outlet 110 through a power cord 120 at inlet 132. Wall outlet 110 can be connected to a 120 Volt Alternating Current (120 VAC) as a power supply voltage, as but one example. Conventional PDU 130 includes eight power distribution outlets (PDO-1 to PDO-8). Each power distribution outlet (PDO-1 to PDO-8) can be connected to a respective load device (LD1 to LD8) through a respective power cord (PC-1 to PC-8).
Conventional PDU 130 also includes a circuit breaker 134. Circuit breaker 134 is connected between the inlet 132 and the power distribution outlets (PDO-1 to PDO-8). In this way, the sum of the currents flowing from each power distribution outlet (PDO-1 to PDO-8) to the respective load device (LD1 to LD8) flows through circuit breaker 134.
Circuit breaker 134 “trips” or becomes an open circuit when the current exceeds the overcurrent rating of the circuit breaker 134. When the circuit breaker 134 trips, the power supply voltage is disconnected from all of the power distribution outlets (PDO-1 to PDO-8) and all of the respective load devices (LD1 to LD8). In this way, even if, for example, load device LD3 is causing the overcurrent condition, all of the other load devices (LD1, LD2 and LD4 to LD8) also are disconnected from the power supply voltage.
Conventional PDU 130 has various drawbacks. For example, in the above-mentioned situation load device LD3 may not be a system critical device. However, load device LD4 may be system critical. In this case, a system critical load device LD4, such as a network server for example, is disconnected from the power supply when a less critical device is causing the overcurrent condition.
Another drawback for conventional PDU 130 is where one of the load devices, for example load device LD5, needs protection at a current lower than the overcurrent rating of circuit breaker 134. For example, load device LD5 could be connected to power distribution outlet PDO-5 with a power cord that is rated to only 5 amps, but circuit breaker 134 can have an overcurrent rating of 15 amps. In this case, load device LD5 may have a current exceeding 5 amps without causing circuit breaker 134 to trip if the other load devices (LD1 to LD4 or LD6 to LD8) collectively draw less than 10 amps. Of course, in the case where only load device LD5 is connected to conventional power distribution unit 130, load device LD5 would not have sufficient overcurrent protection under any condition.
Another drawback for conventional PDU 130 occurs when there is a temporary current surge in one of the load devices (LD1 to LD8). In this case, circuit breaker 134 can trip even though the current surge will not cause an electrical failure to the offending load device (LD1 to LD8). As previously mentioned, when circuit breaker 134 trips, all the load devices (LD1 to LD8) lose power.
In view of the above discussion, it would be desirable to provide a current protection apparatus that may provide individual and/or customized current protection to a load device.
It would also be desirable to provide a method of current protection that may provide individual and/or customized current protection to a load device.
It would also be desirable to provide a current protection apparatus and method of current protection that may provide protection from current surges that may damage an individual load device without unwarranted protection against a temporary current surge that may not be sufficient to cause an electrical failure of a load device. It would further be desirable to provide such protection in a power distribution unit.
It would also be desirable to provide a current protection apparatus and method of current protection for a power distribution unit that may provide individual and customized current protection to each load device connected to a power distribution outlet.
Additionally, a method, system, and apparatus for remote power management and monitoring has been set forth in commonly owned and co-pending U.S. patent application Ser. No. 10/625,837 filed Jul. 22, 2003, U.S. patent application Ser. No. 10/431,333 filed May 6, 2003, U.S. Provisional Patent Application Ser. No. 60/378,342 filed May 6, 2002, Canadian Patent Application Number 2,428,285 filed May 6, 2003, and European Patent Application Number 03252833.3 filed May 6, 2003. The full disclosures of these patent applications are incorporated by reference.